Hi Reinhard, Il giorno mer 12 giu 2019 alle ore 19:02 Reinhard Speyerer <rs...@arcor.de> ha scritto: > > This series addresses the following issues observed when using the > QMAP support of the qmi_wwan driver: > > 1. The QMAP code in the qmi_wwan driver is based on the CodeAurora > GobiNet driver ([1], [2]) which does not process QMAP padding > in the RX path correctly. This causes qmimux_rx_fixup() to pass > incorrect data to the IP stack when padding is used. > > 2. qmimux devices currently lack proper network device usage statistics. > > 3. RCU stalls on device disconnect with QMAP activated like this > > # echo Y > /sys/class/net/wwan0/qmi/raw_ip > # echo 1 > /sys/class/net/wwan0/qmi/add_mux > # echo 2 > /sys/class/net/wwan0/qmi/add_mux > # echo 3 > /sys/class/net/wwan0/qmi/add_mux > > have been observed in certain setups: > > [ 2273.676593] option1 ttyUSB16: GSM modem (1-port) converter now > disconnected from ttyUSB16 > [ 2273.676617] option 6-1.2:1.0: device disconnected > [ 2273.676774] WARNING: CPU: 1 PID: 141 at kernel/rcu/tree_plugin.h:342 > rcu_note_context_switch+0x2a/0x3d0 > [ 2273.676776] Modules linked in: option qmi_wwan cdc_mbim cdc_ncm > qcserial cdc_wdm usb_wwan sierra sierra_net usbnet mii edd coretemp > iptable_mangle ip6_tables iptable_filter ip_tables cdc_acm dm_mod dax > iTCO_wdt evdev iTCO_vendor_support sg ftdi_sio usbserial e1000e ptp pps_core > i2c_i801 ehci_pci button lpc_ich i2c_core mfd_core uhci_hcd ehci_hcd rtc_cmos > usbcore usb_common sd_mod fan ata_piix thermal > [ 2273.676817] CPU: 1 PID: 141 Comm: kworker/1:1 Not tainted 4.19.38-rsp-1 > #1 > [ 2273.676819] Hardware name: Not Applicable Not Applicable > /CX-GS/GM45-GL40 , BIOS V1.11 03/23/2011 > [ 2273.676828] Workqueue: usb_hub_wq hub_event [usbcore] > [ 2273.676832] EIP: rcu_note_context_switch+0x2a/0x3d0 > [ 2273.676834] Code: 55 89 e5 57 56 89 c6 53 83 ec 14 89 45 f0 e8 5d ff ff > ff 89 f0 64 8b 3d 24 a6 86 c0 84 c0 8b 87 04 02 00 00 75 7a 85 c0 7e 7a <0f> > 0b 80 bf 08 02 00 00 00 0f 84 87 00 00 00 e8 b2 e2 ff ff bb dc > [ 2273.676836] EAX: 00000001 EBX: f614bc00 ECX: 00000001 EDX: c0715b81 > [ 2273.676838] ESI: 00000000 EDI: f18beb40 EBP: f1a3dc20 ESP: f1a3dc00 > [ 2273.676840] DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068 EFLAGS: > 00010002 > [ 2273.676842] CR0: 80050033 CR2: b7e97230 CR3: 2f9c4000 CR4: 000406b0 > [ 2273.676843] Call Trace: > [ 2273.676847] ? preempt_count_add+0xa5/0xc0 > [ 2273.676852] __schedule+0x4e/0x4f0 > [ 2273.676855] ? __queue_work+0xf1/0x2a0 > [ 2273.676858] ? _raw_spin_lock_irqsave+0x14/0x40 > [ 2273.676860] ? preempt_count_add+0x52/0xc0 > [ 2273.676862] schedule+0x33/0x80 > [ 2273.676865] _synchronize_rcu_expedited+0x24e/0x280 > [ 2273.676867] ? rcu_accelerate_cbs_unlocked+0x70/0x70 > [ 2273.676871] ? wait_woken+0x70/0x70 > [ 2273.676873] ? rcu_accelerate_cbs_unlocked+0x70/0x70 > [ 2273.676875] ? _synchronize_rcu_expedited+0x280/0x280 > [ 2273.676877] synchronize_rcu_expedited+0x22/0x30 > [ 2273.676881] synchronize_net+0x25/0x30 > [ 2273.676885] dev_deactivate_many+0x133/0x230 > [ 2273.676887] ? preempt_count_add+0xa5/0xc0 > [ 2273.676890] __dev_close_many+0x4d/0xc0 > [ 2273.676892] ? skb_dequeue+0x40/0x50 > [ 2273.676895] dev_close_many+0x5d/0xd0 > [ 2273.676898] rollback_registered_many+0xbf/0x4c0 > [ 2273.676901] ? raw_notifier_call_chain+0x1a/0x20 > [ 2273.676904] ? call_netdevice_notifiers_info+0x23/0x60 > [ 2273.676906] ? netdev_master_upper_dev_get+0xe/0x70 > [ 2273.676908] rollback_registered+0x1f/0x30 > [ 2273.676911] unregister_netdevice_queue+0x47/0xb0 > [ 2273.676915] qmimux_unregister_device+0x1f/0x30 [qmi_wwan] > [ 2273.676917] qmi_wwan_disconnect+0x5d/0x90 [qmi_wwan] > ... > [ 2273.677001] ---[ end trace 0fcc5f88496b485a ]--- > [ 2294.679136] rcu: INFO: rcu_preempt detected stalls on CPUs/tasks: > [ 2294.679140] rcu: Tasks blocked on level-0 rcu_node (CPUs 0-1): P141 > [ 2294.679144] rcu: (detected by 0, t=21002 jiffies, g=265857, q=8446) > [ 2294.679148] kworker/1:1 D 0 141 2 0x80000000 > > > In addition the permitted QMAP mux_id value range is extended for > compatibility with ip(8) and the rmnet driver. > > Reinhard >
I tested your patch-set with LM940 and it seems working properly. If you think it is worth, the tag Tested-by: Daniele Palmas <dnl...@gmail.com> can be added. By the way, not related to your patches, but I've received reports of throughput tests with LM960 (dl-max-datagrams=32,dl-datagram-max-size=16384, single PDN, UDP) reaching around 1.15 Gbps in downlink, so the driver seems to be working pretty well. This, however, requires usbnet rx_urb_size to be changed (currently I'm just modifying the parent network adapter MTU to achieve this). Thanks, Daniele > [1]: https://portland.source.codeaurora.org/patches/quic/gobi > [2]: https://portland.source.codeaurora.org/quic/qsdk/oss/lklm/gobinet/ > > Reinhard Speyerer (4): > qmi_wwan: add support for QMAP padding in the RX path > qmi_wwan: add network device usage statistics for qmimux devices > qmi_wwan: avoid RCU stalls on device disconnect when in QMAP mode > qmi_wwan: extend permitted QMAP mux_id value range > > Documentation/ABI/testing/sysfs-class-net-qmi | 4 +- > drivers/net/usb/qmi_wwan.c | 103 > ++++++++++++++++++++++---- > 2 files changed, 91 insertions(+), 16 deletions(-) > > -- > 2.11.0 >
